Lake



' lowing examples aregiven "Example 1.-100 parts byweight of a 10 per cent hydrate ofalumina paste are mixed- Patented Dec. 27, 1927.

LIUNIKTED STATES 1,653,851 PATENT OFFICE.

nn'rcrr-namnmn, or wmsnonr, mm COLOGNE, GERMANY, ASSIGNOB, Bx mnsNn ASSIGNMENTS, ro ennssnnm mzns'rurrconronnrrorr, or NEW Yonx, N. Y., A

CORPORATION OF DELAWARE.

LAKE.

No Drawing. Application filed. December 27, 1923, Serial No. 688,059, and in Germany May 22, 1928.

taining both tungsten and molybdenum, for

example, molybdenum phosphotungstates and molybdenum silicotungstates.

These products, which so far as I am Q aware, are new, can be obtained by dissolving 90 parts of sodiumtungstate, 10 parts of sodium molybdate and 10 parts of sodium phosphate together in water, heating to boiling. for 15 minutes and precipitating the sodium molybdenum phosphotungstates with concentrated hydrochloric acidand a small 'quantity of concentrated nitric acid. The

yellow'salt gives a colourless water. a

Or 90 parts of sodium tungstate and 10 parts of sodium molybdateare dissolved in water, freshly precipitated silicic acid is added and the mixture is then heated to boiling for one hour. .It is filtered and from the filtrate the sodium molybdenum silicotungstate is precipitated with hydrochloric acid containing a small amount of nitric' acid. l A pure yellow product results, soluble in water to a colourless solution. X 30 generally speaking, derivat1ves of the com 'plex phosphotungstic acid, or its sodium.

\ salt, described in Gmelin-Kraut, Handbuch der anorganischen Chemie; 1912, Vol. III, part 1, page, 823, the formula for which'is given ,as

- 4 the tungsticfcomponent by a mo ybdenum component, and the novel molybdenum silicotungstates herein described are derlved therefrom by replacing the phosphoric component by a'silicic component.

In order' to illustrate my invention the with a solution of 1 part by weight of brilliant green extra dissolved in100 parts by weight of boiling water. A solution of solution in The substances comprisin this group are,

The novel molybdenum phosphotungstates described in the present application the01eti-' molybdenum pliosphotungstate is added until the dye is precipitated.

, The complex sodium molybdenum phosphotungstate obtained according to the above example corresponds substantially to the formula 2Na,o.1 ,o,.24 Wo,+Moo, +aqua, the proportion of WO to M00 being about 9 to 1. In general, the sum total of W0 and M00, components must be 24.

Other basic dyes can'be used, e. g. methyl I violet R and B, Chinagreen, auramine 0..

Example 2. parts-by weight of heavy spar are stirred up with water into a paste like mass, 10 parts by weight of aluminium sulfate (18 per cent A1 0 dissolved in 1.00 partsby Weight of water and then 5 parts by weight of calcined sodium carbonate dissolved in'50 parts by weight of water are added with stirring. Subsequently'the hot aqueous solution of 5 parts by weight .of

brilliant wool blue FFR extraand the aqueous solutionof 2.5 parts by weight of sodi- 'befadded before, after or simultaneously with the .dye.

um molybdenum phosphotungstate are added and the lake is then precipitatedwith a Instead of brilliant wool bln FFR an. other acid dyes, such as for example" acid 1 green GG extra, aeidviolet 4 B extra and R extra can be used, the relative proportions remaining substantially the same.

I claim 1. A lake comprising-a dyestuif having both sulfoand amino groups associated with a complex compound containing tungsten,

molybdenum the anhydl'ide of'one of theg P osphoric acid and it acids of the licic acid, an a substratum, and possessing great fastness towards light, substantially as described.

7 2. A lake comprising a basic dyestufl' associated with v a; complex' compound contain-' of one of the acids of the group phosphoric acid and silicic acid, and a substratum and possessing great fastness towards light, substantially as described.

, ing tungsten, molybdenum, and'ananhydride 3. A lake of great fastness towards light with a molybdenum phosphotungstate compound and a substratum of insoluble barium compound, substantially as described.

6. A lake comprising a basic dyestufi' in combination with a molybdenum phosphotnngstate compound and a substratum of insoluble barium compound, substantially as described.

In testimony whereof I have hereunto set 20 my hand.

' ERICH HARTMANN. 

